The invention relates generally to the field of optical amplifier devices and silicon photonic circuit devices comprising such optical amplifier devices, and, more particularly, relates to optical amplifier devices with active gain layer stacks of III-V semiconductor material layers.
Silicon photonics relate to photonic systems, where silicon is used as a medium for light propagation because of the material's low optical loss. Silicon photonics makes use of well-established silicon manufacturing principles exploited in complementary metal-oxide semiconductor (CMOS) electronics. The features are usually patterned into micro-photonic components with sub-micron precision (to operate in the infrared). Silicon-on-insulator (SOI) is typically used as a material of choice. The fabrication of silicon photonic devices can otherwise involve known semiconductor fabrication techniques; since silicon is already used as a substrate of choice for most integrated circuits, it is possible to create hybrid devices in which the optical and electronic components are integrated onto a single chip.
Integrated optical interconnects with compatible light sources are needed for mass-fabrication of low-cost, high-performance CMOS-based chips. Due to the indirect band gap of silicon, no Si-based light source is available. Efficient light sources are typically based on III-V semiconductors which are heterogeneously or hybrid integrated on a Si photonics platform.
Most promising approaches resort to bonding a full epitaxial III-V-based gain layer stack, or a thin seed layer, which may be subject to successive re-growth, on top of the silicon photonic waveguides. The III-V stack need typically be laterally structured, which requires a sensitive etch step.